Molecular Mechanisms of Patterning the Limb Proximodistal Axis and Quantitative Studies Addressing its Scalability over Five-Fold Changes in Size.

肢体近远轴图案化的分子机制以及解决其尺寸五倍变化的可扩展性的定量研究。

• 批准号: 269024926
• 负责人: Professorin Dr. Elly Margaret Tanaka, Ph.D.
• 金额: --
• 依托单位: IMBA - Institute of Molecular Biotechnology GmbH
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/269024926?language=en
• 关键词: Molecular; Mechanisms; Patterning; Limb; Proximodistal

How animals pattern and scale organ size during development is a fundamental problem in developmental cell biology that also has relevance for engineering tissues for regenerative applications. The vertebrate limb bud is an important model to examine how an appropriately proportioned upper arm, lower arm and hand along the proximal/distal (PD) axis arises but a consensus model does not yet exist. Axolotl limb regeneration provides unique experimental advantages to address this problem. Limb regeneration occurs via the same sequence of HOXA gene induction as in development but more slowly than other vertebrates and it occurs in blastemas from animals >5-fold different in size. Here we use heterochronic cell transplantation, in vivo and ex vivo perturbation of major signalling pathways and CRISPR-mediated knockout of novel apical epithelial genes to test the major limb patterning models and identify the molecular pathways governing HOXA11 and HOXA13 induction. We then use this information to test three hypotheses of how limb patterning scales over a 5-fold range in limb field size.

动物在发育过程中如何塑造和衡量器官大小是发育细胞生物学的一个基本问题，也与再生应用的工程组织有关。脊椎动物肢体芽是研究上臂、下臂和手沿近端/远端（PD）轴的适当比例如何产生的重要模型，但尚未存在共识模型。蝾螈肢体再生为解决这一问题提供了独特的实验优势。肢体再生通过与发育中相同的HOXA基因诱导序列发生，但比其他脊椎动物慢，并且发生在大小相差5倍的动物的胚母中。在这里，我们使用异慢性细胞移植，体内和体外主要信号通路的扰动和crispr介导的新型顶端上皮基因的敲除来测试主要的肢体模式模型，并确定控制HOXA11和HOXA13诱导的分子途径。然后，我们使用这些信息来测试肢体图案如何在肢体场大小的5倍范围内扩展的三个假设。